As integrated circuitry device dimensions continue to shrink, problems such as short channel effects, source-drain punchthrough, and hot electron susceptibility become ever present, particularly in the deep sub-half-micron regime. These effects have, in the past, been addressed by additional masking levels and through the incorporation of lightly doped drain (LDD) engineering.
This invention arose out of concerns associated with providing improved integrated circuitry devices while reducing problems associated with short channel effects, source-drain punchthrough, and hot electron susceptibility, particularly in the deep sub-half-micron regime.